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Jafferis, William

Publications and source records attributed to Jafferis, William.

Applications of triggered lightning to space vehicle operations

Kennedy Space Center (KSC) and the USAF Eastern Space Missile Center (ESMC) covering an area of 25 x 40 km are frequently called America's Spaceport. This title is earned through the integration, by labor and management, of many skills in a wide variety of engineering fields to solve many technical problems that occur during the launch processing of space vehicles. Weather is one of these problems, and although less frequent in time and duration when compared to engineering type problems, has caused costly and life threatening situations. This sensitivity to weather, especially lightning, was recognized in the very early pioneer days of space operations. The need to protect the many v\facilities, space flight hardware, and personnel from electrified clouds capable of producing lightning was a critical element in improving launch operations. A KSC lightning committee was formed and directed to improve lightning protection, detection, and measuring systems and required that all theoretical studies be confirmed by KSC field data. Over the years, there have been several lightning incidents involving flight vehicles during ground processing as well as launch. Subsequent investigations revealed the need to improve these systems as well as the knowledge of the electrical atmosphere and its effects on operations in regard to cost and safety. Presented here is how, KSC Atmospheric Science Field Laboratory (AFSL), in particular Rocket Triggered Lightning, is being used to solve these problems.

Jafferis, William↗

Measuring Effects Of Lightning On Power And Telephone Lines

Spherical antenna senses both horizontal and vertical fields simultaneously. Measures "fast" components of electric field used in conjunction with other equipment, including antenna measuring "slow" vertical component of electric field; microphone that senses thunder; cameras making visual records, which locate lightning; magnetic-field sensor; optical sensors; and instruments measuring speed and direction of wind.

Jafferis, William↗

A case study of a low lightning rate storm during the Florida winter

Meteorological and cloud electrical data collected during a winter storm on January 21, 1988 at the Kennedy Space Center (KSC) in Florida are presented. A pronounced transition from area-integrated convergence to divergence with associated peak electrical activity was observed, which appears to be characteristic for both the summer and the winter storms at KSC. The mesoscale precipitation region behind the squall line was substantially electrified over an area far larger than the KSC complex. It is noted that, in such a situation, the accumulated electric charge and peak lightning currents may be an order of magnitude greater than those encountered in isolated summer thunderstorms, and the lightning hazard is correspondingly greater.

Williams, Earle R.↗

Atmospheric sciences program at NASA Kennedy Space Center

A very keen awareness of the impact of lightning threat on ground operations exists at NASA Kennedy Space Center (KSC) because of the high frequency of thunderstorm occurrences in Florida. The majority of thunder events occur in the summertime, initiated by solar heating of the land. Merritt Island, where KSC is located, produces its own thunderstorms under light flow conditions; because some are small, their importance might be unappreciated at first glance. The impress of these facts, and others of pertinence, on the KSC atmospheric sciences development program will be discussed, priorities enumerated, and a review of development projects presented.

Nicholson, James R.↗

Atmospheric Science Field Laboratory - A feasibility study

Plans are underway to transfer the technology represented by the lightning and atmospheric science research facilities and capabilities at the Kennedy Space Center to outside users in other government agencies, private industry, and the academic community. Rocket triggered lightning is being used to demonstrate the feasibility of establishing an Atmospheric Science Field Laboratory as a permanent facility and long-term cost sharing. Results from previous programs and data from a lightning event which occurred during the STS-7 flight are presented to demonstrate the adequacy of the present lightning protection and measuring system to protect personnel, vehicle, and ground equipment, as well as to rapidly assess damage due to a lightning event.

Jafferis, William↗